Despite tremendous progress in psychology and neuroscience, physical therapists treating patients with stroke still rely on unspecific guidelines to determine task practice schedules for functional motor skill reacquisition. The present proposal is novel in defining specific rehabilitation practice protocols derived from psychological learning theory, with particular emphasis on the "micro-scheduling" of the practice trials to enhance learning. Previous research in word-learning and motor skill learning shows that practice schedules 1) in which the task presentations are variable, or 2) in which the intervals between presentations of individual tasks are expanded, significantly enhance long-term retention and generalization of learning. In this pilot study, the PIs use a manual grasping task, and propose to demonstrate with participants who are recovering from stroke-hemiparesis that massed, random, and expanded variable practice schedules affect differentially the acquisition performance and the learning of motor skills. Further, using a stratified experimental design, they aim to show an interaction between practice schedule and impairment severity such that the best practice schedule depends on stroke severity. The hypothesis is that subjects with mild deficits benefit most from expanded variable practice, whereas subjects with moderate deficits benefit most from massed practice schedules. [unreadable] [unreadable]